Question

$x { }^{2} - x - 6 = 0$

Answer 1

$x {}^{2} - x - 6 = 0 \\ d = 1 {}^{2} + 4 \times 6 = 1 + 24 = 25 \\ \sqrt{25} = 5 \\ x1 = \frac{1 - 5}{2} = \frac{ - 4}{2} = - 2 \\ x2 = \frac{1 + 5}{2} = \frac{6}{2} = 3$